Air-cooled gas-engine.



PATENTED MAR. 31, 1908.

C. B. KURTZ. AIR GOOLED GAS ENGINE.-

A PILIOATION FILED AUG; 27. 1906.

INVENTOR WITNESSES:

O AITORNEV PATENT OFFICE.

AIR'COOLED GAS-ENGINE.

Specification of Letters Patent.

Patented March 31, 1908.

Application filed August 27, 1906. Serial No. 332,127.

To (til whom ifv may concern.

Be lt known that l, (Fruits I). KURTZ, e

citizen of the United States, resident of' Cleveland, county of Cuyohoga, und State of Ohio, have invented it new and useful lm movement in Airifooled (.ln.s-l-higines, of which the following is specification, the principle of the invention being herein explained and the best mode in which I here contemplated applying that 'm'ineiple so as to distinguish it from other invcntioi'is.

lily invention relulcs to improvements in explosion motors und particularly in explosion motors of the air-cooled type.

The object of my invention is to provide a motor in which not only the cylinder but also the piston. may be kept at the proper temporulurc without the of any cooling agent other than air.

Another object is the provision ol' means whereby the engine may be coupled up more closely to thTl crankshaft, thus econon11 ising space.

'lio the uccomplislunent of these and related ends said invention consists of the line ns hereinafter fully described and spech coll y set forth in the claims.

'lhe dnnexed drawing and the following description set forth in detail certain means en'ibodying the invention, such disclosed in one constituting but one of various melltrzili liOlllflS in which the principle of the tion may be used. id annexed (ll'ttwil'lgl Figure l rep-- resents partly in side elevation, and partly in ind cross-:5; :tion es cut by it plane at to the line of the crunla-slanft, or four cycle gins-engineembodying ni screrztl improvements llig. i2 is an axial notion of such engine as cut by u plunc l'lllZ tin-(nigh the line of the crunl;shaft; o trenswnso crossseciion tnlrcn on through line It 5, ig. 1;

bottom plan view of the. 1.1+ s feature of my improvznl s has been irulicotod, l. lHtVU chosen on tltto or lom'--cycie engine for the purpose ol illustrnlmg my n'ivcntion. liovrevor, it

should be fully llvltltlll't from Wllitt follows th' such "option is inst as readily susc ol incorporation ill at lwo-cycle as in. lo vrlo engine. .ihnthor is it lmntcd to EU connnmi but it sm le c lindcr, A l w b us in the ease oi the one shown, but engines of any number of cylinders, alined or opposed, may be built on the lines of the invention.

From an inspection of the several fi ures of the drawing; it is seen that the cylin er 1.;

of my improved engine is open at both. ends.

Such cylinder, furthermore, instead of being of {t uniform bore throughout, comprises two uni-Lilly elined portions I), I) of different diameters. The exterior surface of the lower portion l) of the cylinder, the one of larger diameter, is preferablystudded with flanges b, or equivalent hcnt radiating members; and the upper portion may also be similz-rrly provided with flanges, if so desired, although in the particular engine here illustrated their use thereon is deemed unnecessary.

Within the cylinder is reciproeztbly mounted a hollow piston A, freely open at both ends and comprising two portions a (1 respectively fitted to the two portions 7; b of the cylinder. Each. of these piston portions (1 a is formed with :1 bearing surf are provided with piston rings of of the usualdesign whcrebyo tight fit is bad with thdcylindcr bore. The obvious result of the c nstruction just forth is the formation of an annular colnb'ustion ol'iumber (l of varying volume do pending upon the. position of the piston Withiiti the cylinder. i Such combustion chnn'iber U is provided. with inlet end or llzit'LlSt ports for the admission of the charge and the expulsion ol the spent gas-cs such are ordinztril y em ploycd in this connection.

lly nothing the piston hollow and open at both ends uv (lll'UUllblUll of air through the Sillllt} of such velocity as will be conducive of best results can be nminioined by employing an air blast developed by it fun in the usual wey or preferably by u blower especiull'y provided for the purpose in connection with each engine cylinder. The interior wells of the piston, or least those portions thcrwl. which inclose combustion chamber that the engine can be con led much more closely than in the standard type of motor. This will be readily apparent from an inspection of the figures, particularly Fig. 2, where it is seen that the base of the cylinder sets almost upon the crank-shaft i). This is made possible by the fact that the upper end of the connecting-rod D can be attachedanywhere to piston A, such attachment in the case illustrated being made not only beyond the combustion chamber but to ears 0; formed on the end of the portion of the pis ton of smaller diameter, which ears are adapted to project entirely without the cylinder as the piston reaches the upper limit of its stroke. Inspection and lubrication of connectin -rod pin d is thus greatly facilitated, ttIN its removal made possible without the necessity of disassembling the engine. In addition to the desirable results just noted as being achieved by the foregoing construction it may be pointed out in conclusion that by having the piston hollow and coupling the connecting rod thereto beyond the combustion chamber not only is a longer throw for given height of engine achieved than has been possible in the resent design. of engine, but two separate bearing surfaces for the piston are provided, thus decreasing its tendency to cant .due to the angularity of the connecting rod and reducing the frictional loss to a minimum. The compactness of the engine will particularly commen l it in the case of engines of the opposed type for automobile use, since it will now be pos- -sible to construct such engines short enough to be readily accommodated transversely of the automobile frame.

Having thus described my invention in detail, that which I particularly point out and distinctly claim is:

In an explosion motor, the combination with a crank-shalt and connecting-rod of a cylinder open at both ends and comprising two )ortions having dill'crcnt diameters; and a hollow piston comprising two bearing portions 'litted to the two portions of said cylinder, respectively, the portion of said piston having the smallerdiameter being adapted in said pislons upper position to project with out said cyliiulcr and said connccting-rml being attached to such portion whereby the pin holding said connecting rod may be rc-. moved without wit hdrawing thc'piston from the cylinder.

2. in an explosion motor, the combination with a crank-slml't and cmmecting rod; of a cylinder open at both ends and comprising two portions having dill'erent diameters; and a l ends and comprising two bearin l l iollow piston likewise open at both fitted to the two portions of saic cylinder, respectively, the portion of said piston having the smaller diameter being adapted in said pistons ,upper osition to project without said cylinder and said connecting-rod being attached to such portion whereby the pin holdingsaid connecting-rod may be removed without withdrawing the piston from the cylinder.

3. In an explosion motor, the combination with a cylinder open at both ends and com-- prising two portions having different diameters, of an annular piston fitting in the larger of said cylinder )ortions, and provided on one side with a tu in the smaller of said cylinder portions, whereby an annular explosion chamber is formed, the inner surface of said larger cylinder or-tion being ex weed to the air save for tie portion included within such annular chamber.

4. In an explosion motor, the combination with a cylinder open at both ends and comprising two portions having dill'erent diameters; of an annular piston fitting in the larger of said cylinder portions and provided on one side with a tubular extensionfitting in the smaller of said cylin .ler portions, whereby an annular explosion chamber is formed, the inner surface of said larger cylinder portion being exposed to the air save for the portion included n-ithin such annular chamber; a crank-shaft located opposite the larger end. of said cylinder; and a connectii'ig rod joining said shaft to end. of said eon'neetin rod being attached to the tubular portion or said piston.

In an explosion motor, the combination with a cylinder open at both ends and comprising two portions having different diameters, of an annular piston fitting in the larger of said cylinder portions, and provided on one side with a tubular extension fitting in t 1e smaller of said cylinder s iai't located substantiallv directly against the larger-end of said cy inder, and a coin necting rod joining said shalt to said piston, the outer end of said connecting rod being attached to the tubular portion ol ton, and the throw of said cranleshal't being sullicient to cause said outer rod end to i ject without the cylinder at the end 0;! pistons outward stroke,

i ned by me, "this 24th day of August it) Vi inwnLL,

- OBERLIM.

portions said piston, the outer portions, a cranlosaid pis- 'ular extension fitting 

